Dang, I still can't access jhuapl and a number of other U.S. sites from here in Taiwan. Does anyone else have a similar problem? The Cassini site is also inaccessible to me most of the time recently. I complained to my ISP and they actually blamed it on the Japan earthquake - but tracert indicates the problem is somewhere in the U.S. I thought the Internet was designed to be robust in the face of point blockages whatever the cause. Anyway I hope there will be plenty of secondary renderings springing up on this thread and elsewhere, before the "oohs" and "aahs" drive me nuts! Thanks Hugh, for your offering in 93 - spectacular.

You can always try a proxy. Sometimes intermediate DNS caching screws you. For awhile I couldn't access my college's domain from my employer's network. Sending a few emails went nowhere on that one, too.

This may be an odd question. Maybe I've misunderstood the science here. But is MESSENGER expected to markedly improved the ephemerides of Mercury and other solar system bodies?

Something I've been interested in (very casually! not a scientist!) is the accuracy of our knowledge of the planet's positions, and how folks use them to make statements about orbital stability and solar system masses and stuff like that. (eg. this PDF)

Is this supposed to be no improvement, a minor improvement, or a major improvement? Are there any specific results expected or hoped for?

Ranging and Doppler might make some improvements to the orbit data, and the rotation axis orientation, though maybe not much improvement over what radar has already given us. Other bodies? - I can't see that. The questions you are interested in are probably addressed most thoroughly with radar, at least out to Saturn's orbit. Goldstone and Arecibo routinely do radar ranging and doppler for solar system targets.

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